Every high school science teacher or laboratory technician who has spent an appreciable amount of time in a laboratory has undoubtedly heard the cacophonic crash of crucibles, test tubes, and other laboratory glassware being dropped and shattered. Oftentimes, these accidents occur because the art has not yet developed a device for safely handling hot hazardous objects, such as crucibles, flasks, and test tubes; securely standing them in place; and allowing them to be safely placed over a hot plate, gas hot plate, open flame, or other laboratory heating apparatus.
The current state of the art is to use crucible tongs, the common device for handling crucibles, in a laboratory. Crucible tongs, which operate in the same manner as common tongs, feature pincer shaped, curved levers at the distal end of the tong, which are designed to more securely handle the crucible. Because the tongs commonly are made from steel, and crucibles commonly are made from ceramic, which are both smooth, low-friction materials, the crucible is susceptible to slipping through the tongs, falling, and breaking.
A variety of tongs have been developed to better handle crucibles. One configuration, for example, uses a piece of plastic or rubber at the distal end of the tongs in order to allow a better friction grip of the crucible. The additional rubber and plastic can lead to complications, however, because the high heat content of heated crucibles can burn the rubber or plastic and contaminate the reactants. Also, the rubber or plastic can become otherwise worn by repeated use in the laboratory. And, of course, the material kept in the crucible may corrode the rubber or plastic. Further, because one needs to squeeze the tongs in order to apply pressure to the crucible while, simultaneously, moving one's arm in order to move the crucible, the use of these tongs requires a relatively substantial degree of dexterity, so as not to drop or crush the crucible.
Another device, commonly referred to as a “test tube clamp” or “Stoddard Clamp” operates on the same principle as a tong, with the added feature of a spring mechanism. The spring serves to ease operation by applying pressure to hold the test tube or flask as it is carried by the user, thus demanding less manual dexterity. These Stoddard Clamps, however, are limited because, while they function to carry test tubes and flasks, they are not well suited to handling crucibles, which often must be tilted on their side in use. Further, they cannot be used to stand the labware on a flat surface, in or over a flame, or above another heating apparatus.
Another device that can be used to support test tubes and crucibles is commonly referred to as a support stand and ring. These devices consist, generally, of a high-mass base, a pole, and a ring or clamp for holding the test tube, flask, or crucible that can be slid up and down the pole. While these devices provide a secure means of supporting a test tube, flask, or crucible, the movement is limited to up and down the pole. Thus, these devices are not well suited to handling test tubes and crucibles while moving them around the laboratory.
Another device that can be used to carry crucibles, but not to stand them up, is commonly referred to as a triangle. This device consists of a triangle shape made from twisted wire with three sides that are each encased in a clay pipe sleeve. While the triangle provides a suitable means for standing crucibles on a ring stand, it has several shortcomings. First, because it does not have vertical legs, it cannot be used to stand the crucibles on a flat surface. Thus, it must always be used in conjunction with a ring stand or other such stand. Second, the triangle is susceptible to falling off of the ring stand because it lacks a safety mechanism to prevent it from slipping or being knocked off of the ring stand. Third, the triangle lacks an insulated handle or any other suitable means for carrying the crucible. Thus, the triangle is difficult to handle and can easily be dropped, resulting in possible loss of the reactants, damage to the crucible, and the user's exposure to dangerous materials. A triangle simply does not perform the tasks needed.
Thus, there has been a long felt need in the art for a device that can securely support a crucible, test tube, or flask, be easily and safely handled by the user, and will allow the crucible, test tube, or flask to be safely supported on a flat surface, over a flame, or other laboratory heating apparatus.